Relationship of the WISC-III and WISC-R for Students with Specific Learning Disabilities and Mental Retardation

Abstract

The relationship between WISC-R IQs and WISC-III IQs was examined in two samples of students with disabilities. One sample (n = 64) consisted of students with specific learning disabilities (SLD); the other sample (n = 55) consisted of students with mental retardation (MR). All students were enrolled in special education classes and were undergoing routine three-year reevaluations. With the exception of the correlation of Performance IQs for students with MR, which was nearly identical to the correlation reported in the WISC-III manual, the correlations between the WISC-R and WISC-III IQs were lower than those reported in the WISC-III manual. In addition, Verbal, Performance, and Full Scale IQs on the WISC-III were significantly lower than the previously obtained scores on the WISC-R for both students with SLD and those with MR. These differences were generally consistent with the differences reported in the WISC-III manual.